1. Field of the Invention
present invention relates to a focal-length switchable photographic camera, and more particularly to a photographic camera having a focal length changeover mechanism for switching a focal length of a photographic lens, a linking member for operatively connecting the focal length changeover mechanism to a motor and a lens cover for covering and uncovering a front face of the photographic lens.
2. Description of the Prior Art
In the case of the above-described type of camera, it is a known arrangement to provide a manually operable cover opening lever for opening and closing a lens cover. More specifically, there is also provided an operative member having a cam face and there is implanted in the lens cover a pin for coming into contact with the cam face. And a spring is provided for urging the lens cover to be freely openable.
In operation, when the cover opening lever is manually shifted, the cam face of the operative member depresses the pin of the lens cover thereby closing the lens cover against the urging force of the spring. On the other hand, when the cover opening lever is reversely shifted, the depression between the cam face and the pin is released thereby opening the lens cover by means of the urging force of the spring (e.g. Japanese patent application publication under 60-78432).
In the case of so-called compact cameras, it is known that the opening and closing operations of the lens cover are automatically carried out with the lens cover being operatively connected with a film winding-up motor.
However, there are problems as follows with the above-described prior-art arrangements.
Referring to the former arrangement in which the lens cover is opened and closed by means of the manually operable member, this type of manually operable member is usually disposed at a position readily operable by a user's finger, the position being distant from the lens cover. Because of this, a mechanism for operatively connecting the cover and the member tends to be complicated and also to adversely effect the positional arrangement of other units inside the camera. On the other hand, if the manually operable member is positioned adjacent the lens cover, the same is difficult to operate by the finger.
Problems with the latter arrangement in which the, lens cover is opened and closed being operatively connected with the film winding-up motor will be described next. Since the film is wound up by the rotation of the motor and this film winding-up operation is carried out for each photographing operation, in order to open and close the film cover by the rotation of the film winding-up motor, it is necessary to provide in the transmission mechanism for opening and closing the lens cover a clutch for disengaging the operative connection between the cover and the motor during a film winding-up operation. Therefore, such transmission mechanism tends to be complicated.